CBSE 2023 · Region 5 · Set 1 · Q27 · 3 marks
An alternating voltage of $\displaystyle 220$ V is applied across a device X . A current of $\displaystyle 0.22$ A flows in the circuit and it lags behind the applied voltage in phase by $\displaystyle \pi / 2$ radian. When the same voltage is applied across another device Y , the current in the circuit remains the same and it is in phase with the applied voltage.(i)Name the devices X and Y and,(ii)Calculate the current flowing in the circuit when the same voltage is applied across the series combination of X and Y .
An alternating voltage of $\displaystyle 220$ V is applied across a device X . A current of $\displaystyle 0.22$ A flows in the circuit and it lags behind the applied voltage in phase by $\displaystyle \pi / 2$ radian. When the same voltage is applied across another device Y , the current in the circuit remains the same and it is in phase with the applied voltage.
(i)
Name the devices X and Y and,
(ii)
Calculate the current flowing in the circuit when the same voltage is applied across the series combination of X and Y .
Marking-scheme solution
(ii)
(i) X is inductor
Y is resistor
(ii) \(\displaystyle X_{L}=\frac{220}{0.22}=1000 \Omega\)
\[R=\frac{220}{0.22}=1000 \Omega
\]
\[I_{r m s}=\frac{V_{r m s}}{\sqrt{X_{L}^{2}+R^{2}}}
\]
Alternating CurrentAC Voltage Applied to a Series LCR CircuitApplyshort_answermedium
More from Alternating Current
- An alternating current is given by I=I 0 cos (100 π) t. The least time the current takes to decrease from its…2025 · asked 3×
- A resistor of 30 Ω and a capacitor of 250/(π) μ F are connected in series to a 200 V, 50 Hz ac source.…2023 · asked 3×
- An inductor, a capacitor and a resistor are connected in series across an ac source of voltage. If the…2023 · asked 3×
- Assertion: A series LCR circuit behaves as a pure resistive circuit at resonance. Reason (R): At resonance, X…2025 · asked 3×
- How does the resistance differ from impedance? With the help of a suitable phasor diagram, obtain an…2023 · asked 3×
- Assertion: In an ideal step-down transformer, the electrical energy is not lost. Reason (R): In a step-down…2025 · asked 3×
- An ac voltage is given as v=14 sin (314 t) V. The average and the effective value of the voltage (in V ) over…2026 · asked 3×
- The figure shows the variation of capacitive reactance (X C) of two ideal capacitors of capacitances C 1 \& C…2026 · asked 3×
CBSE Class 12 Physics past-paper question from the 2023board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.